Achondroplasia

Symptoms/ Effects

• It is characterized by abnormal bone growth which causes short stature.
• The arms and legs are usually disproportional to their bodies.
• They often have heads that appear too large for their bodies and massive foreheads.
• Most individuals with achondroplasia reach an adult height of about 4 feet.
• Individuals with this condition have relatively long and narrow torsos.
• It also may include the underdevelopment of mid-face.
• The fingers have a 3-pronged appearance similar to a trident.
• Most joints are able to extend more than normal with the exception to the elbows and hips which have limitied extension.
• Enlargement of the brain is common with this condition.
• There are some distinct facial characteristics that are associated with this disease.
• At a young age, the motor skills that come with certain ages are often delayed ; crawling, walking, etc.
• The intelligence of the individual and the life span are often not affected.
• The risk of infant death is increased with the compression of the spinal cord and obstruction of their airways.
• They often have bowed legs.
• This condition may come with a curvature in the spine and clubbed feet.
• Fluid may build up in the brain which is called hydrocephalus.
• People with achondroplasia are more prone to ear infections and are often extreme.
• Dental problems are also very common and require a special dentist.

http://www.achondroplasia.co.uk/pictures/emilyrose.jpg

Mexican family with the disease http://www.mun.ca/biology/scarr/Human_Achondroplasia.gif

Type of Genetic Disorder

• This is an autosomal dominant trait.
• It is caused by the mutation in the gene called fibrolast growth factor receptor 3.
• In about 80% of cases, it is not inherited but results in a new mutation that occurs in a sex cell.
• In about 20% of cases, it is inherited from a parent who also has the condition.
• It is caused by a mutation on the 4th chromosome.

Diagnosis

• At birth or at a young age it is diagnosed using x-rays and physical examinations.
• If suspicion arises of the condition, genetic testing can be done using blood samples to look for a mutation in the gene that causes it.
• It may also be detected in the fetus during an ultrasound examination which may show shortened bones and other bone abnormalities.

Treatment

• There is no cure for achondroplasia.
• It is a new mutation so there is no real treatment available.
• Occasionally surgery is carried out to increase the height or severe bone abnormalities, but this is often painful.
• They may take growth hormones to increase their height.
• Surgery is sometimes necessary to correct skeletal deformities.

Prognosis

• 2 to 5 percent of newborns with this disease do not live past their first year of life.
• Most people have a normal lifespan with normal intelligence levels.
• As age increases, the amount of complications concerning the disease also increases. It is a direct relationship.

Statistics

• About 1 in 20,000 children are born with achondroplasia.
• It affects all races and ethnic backgrounds.

http://www.lpad12.org/Images/Family_Roloff.jpg

Interesting Facts:

• There is a show called "Little People Big World" on TLC which stars a family who has 2 parents with achondroplasia and 4 kids but only 2 of the kids have achondroplasia and the other two are "normal".
• Achondroplasia means "without cartilage formation".
• It is one of the most common form of dwarfism affecting more than 80% of little people.
• Most people with Achondroplasia are double jointed.
• Infants who are homozygous for Achondroplasia rarely live beyond a few months.

Bibliography:

Francomano, Clair. "Achondroplasia". University of Washington. 4/2/08 <http://www.geneclinics.org/profiles/achondroplasia/details.html>.

UMMC, "Achondroplasia". University of Maryland Medical Center. 4/3/08 <http://www.umm.edu/ency/article/001577.htm>.

A.D.A.M, "Achondroplasia". Health Scout. 4/5/08 <http://www.healthscout.com/ency/1/001577.html>.


Comments:

WOW! These facts are super! We were really surprised that dwarfs have trident fingers. One little problem we found was that the picture of the little chica is not cited. Please correct this little mishap. DK and EE

Your page looks great! You forgot to capitalize the word "occasionally", under treatment, so we did that. However, your facts and layout are very good! -Color Blindness

It's interesting there is a TV show focusing on people with Achondroplasia. You might want to put captions under the pictures. Otherwise its looking good. PB and CB

This is a very interesting disease. It is rare that a disorder that's autosomal dominant, so we found this interesting. It is also hard to believe that there is so new a mutation that doctors haven't had time to find a cure yet. With advanced medicine of today, you'd think there would be a cure or at least a treatment coming along soon. I wonder why their heads are disproportional to their bodies and why it is usually the result of a mutation and is not always just passed down.
- Hemophilia

It's very interesting that only 20% of all cases are inherited from a parent. Your page looks very nice. CV-2-CL & CV-2-JH

Wow! great comments! I agree about adding captions in your own words to go along with the images - check out what other people in your class did with that. Your teacher!

The page looks very good. It's very well organized and very easy to follow. That very interesting that the is a show about Achondroplasia.
-Cretinism

Awesome facts, you can tell that you did a lot of research to find out about this disorder. I never knew that "Little People, Big World" was based upon this disease, I find that very interesting. You have many good pictures on here too! Great Job! -KF&LF

Superb job, kiddos! This page was very informative, and the pictures made us swoon with delight. It made us feel a connection to the Roloff Family (of Little People, Big World). Like this:

http://culturekitchen.com/files/images/crossed_fingers_0.thumbnail.jpg

.. We only found one spelling error, "arises," which we promptly corrected! - Cri du Chat (RS & UP)